On 11/25/2012 04:07 PM, Mark H Weaver wrote:
> * Significant change: Fix the NaN problem by making sure that
> two numbers can only be /substantially different/ if at
> least one of them is numerically equal to itself.

IMO this does the wrong thing if you have two different NaN values,
as allowed by IEEE. Neither is numerically equal to itself,
but they have different bit-patterns, and eqv? should compare
them as false.